So a dumb question - within Visual Studio, once I've made the changes per the link above, do I need to do a Build or something to get the changes spelled out to take effect within IIS? What am I still missing?

Also, after doing the websitecopy.exe (which seemed to work fine) I then copied all of the files in my c:/custportal/installation/website/Customer-Portal-R2/website folder over to where the accelerator seemed to get installed at c:/program files/Microsoft
Dynamics CRM Customer eService Portal. This folder in program files is where I did the VS modifications. Is that right?

The error you are getting is for the CRM connection string. The error message feels like your CRM connection string is using Passport authentication, which would imply it is pointed at a valid CRM Online organization, but from the rest of your email,
it sounds like you are using an on-prem install of CRM. This feels inconsistent. Can you confirm your CRM connection string in the web.config of your portal site? If you are using the demo VPC, it should be using Authentication Type=AD and
the server url should be something like http://crm/contoso